73916581 has 4 divisors (see below), whose sum is σ = 73978732. Its totient is φ = 73854432.

The previous prime is 73916573. The next prime is 73916597. The reversal of 73916581 is 18561937.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 18561937 = 109 ⋅170293.

It can be written as a sum of positive squares in 2 ways, for example, as 6002500 + 67914081 = 2450^2 + 8241^2 .

It is a cyclic number.

It is not a de Polignac number, because 73916581 - 2³ = 73916573 is a prime.

It is a super-2 number, since 2×73916581² = 10927321893459122, which contains 22 as substring.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (73916501) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 29256 + ... + 31681.

It is an arithmetic number, because the mean of its divisors is an integer number (18494683).

Almost surely, 2^73916581 is an apocalyptic number.

It is an amenable number.

73916581 is a deficient number, since it is larger than the sum of its proper divisors (62151).

73916581 is a wasteful number, since it uses less digits than its factorization.

73916581 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 62150.

The product of its digits is 45360, while the sum is 40.

The square root of 73916581 is about 8597.4752689380. The cubic root of 73916581 is about 419.6758288445.

The spelling of 73916581 in words is "seventy-three million, nine hundred sixteen thousand, five hundred eighty-one".